Test tube closure



Jan. 5, 1965 E. J. TOWNS TEST TUBE CLOSURE Filed Oct. 16, 1963 UnitedStates Patent Office 3,164,279 TEST TUBE CLGSURE Edward J. Towns,Livingston, N.J., assignor to C. R. Bard, Inc., Murray Hill, N.J., acorporation of New York Filed Oct. 16, 1963, Ser. No. 316,744 6 Claims.(Cl. 215-47) This invention relates to a test tube closure, andparticularly a closure for a culture container, having for an object theprovision of such a closure which comprises a top and a pair ofdepending skirts, the inner one of which is designed and adapted to fitwithin a plain cylindrical tube and is so formed that, when partlyinserted therein, the assembly or unit may be evacuated of air andfilled with a sterilizing gas, while the farther insertion causes theclosure completely to seal the tube; the other I and outer skirt, whichis for manual operation, being spaced from the inner one so as to fitfreely about the exterior of the tube and thus avoid preventing theingress of gas when the tube is being sterilized. The inner skirt islonger than the outer one in order to accommodate the formationsnecessary for the above mentioned functions, while the length of theouter skirt is merely sufficient for convenient handling when insertingthe closure to its partial and complete sealing positions and whenremoving the closure for repeated use of the assembly or unit.

Another object is the provision of such a dual skirted closure that isfitted functionally to cooperate with a cylindrical tube which is devoidof any structural configuration for coaction with the closure, and thusis equally adapted for use with tubes having either unthickened orbeaded open ends.

Another object is the provision of such a closure that is formed with afiat top of considerable area to permit standing the same on one endwith the usual swab sticks that are attached to the top extendingupwardly without danger of contamination while preparing the patient forthe taking of a culture specimen.

-Another object is to provide the top with a projecting edge that isshaped to prevent rolling of the assembly or unit when placed on itsside.

A further object is to provide certain improvements in the form,construction and arrangement of the features or functional elements ofthe closure whereby the above recited objects, and others inherent inthe invention, may be efiiciently attained.

A practical embodiment of the invention is shown in the accompanyingdrawing, wherein FIG. 1 represents a perspective view of the completeassembly or unit;

FIG. 2 represents, on an enlarged scale, a view looking toward thebottom or open end of the closure;

FIG. 3 represents a similar view looking toward the top of the closure;

FIG. 4 represents, on the same scale, a broken perspective View of theclosure alone; and

FIG. 5 represents, on a still larger scale, a sectional view taken onthe line V-V of FIG. 2, looking in the direction of the arrows.

In brief summary, this invention contemplates a cylindrical, dualskirted cap, of which the inner skirt is intended to be inserted withinthe open end of a test tube, and is formed with a pair ofcircumferential longitudinally spaced beads that are adapted closely tocoact with the inner surface of the tube for holding the cap in twopositions in one of which there is partial closure of the tube and inthe other of which there is complete closure or sealing. The inner beadis interrupted by a longitudinally disposed groove that serves to opencommunication between the inner body of the tube and the outer bead,while the latter is continuous and serves tightly to seal the tube whenin contact with the inner surface thereof. Thus the cap may first beinserted to such an extent that the interrupted head is within the tubewhile the continuous bead is without. In this first position the tubemay be evacuated of air and filled with a sterilizing gas due to thepresence of the longitudinal groove. Thereafter, the cap may be fartherinserted into the tube to its sealing position in which the outercontinuous bead closely contacts the inside of the tube while the innersurface of the top of the cap presses upon the edge of the open end ofthe tube. The top of the cap is enlarged in area to permit standing onend and its corners project to inhibit rolling when the assembly or unitis on its side. The tube is composed of a transparent plastic, e.g.polystyrene, to allow visual inspection of its contents, while the capis composed of any suitable plastic that has a slight elastic quality toenable the outer skirt to ride over any enlargement that may exist atthe open end of the tube, and is preferably opaque. Within the innerskirt and fixed thereto is a head piece provided with one or moresockets for receiving the end or ends of one or more swab sticks andholding the same in place with their swabbed end or ends in the tube.

Referring now to the drawing, the tube, which is of the usual test tubeshape, i.e. with the closed end rounded, is denoted by 1, and the cap asa whole is marked 2. In FIG. 1, the assembled tube and cap are shown asresting on a fiat surface 3, such as a table, to illustrate thenonrolling characteristic above mentioned.

The cap has a relatively enlarged top constituted by a surroundingflange with laterally projecting corners indicated by 4, 4, 4, 4, whicheliminate any rolling when the assembly or unit is on its side, aspreviously described; while the center of the top is depressed, as wellshown in FIG. 5, in order to promote sealing contact with the tube edgewhen the cap is in closed position. I

A cylindrical inner skirt 5 is formed integrally with g and projectsdownwardly from the cap top 2, and has a pair of circumferential beadson its outer surface which are longitudinally spaced, the outer head 6being continu ous while the inner one 7 is interrupted or broken by alongitudinal groove 8, the lower end of which is at the inner edge ofthis skirt and the upper end of which terminates short of the head 6.The purpose and function of this groove is to open communication betweenthe interior of the tube 1 and the space between the beads 6 and 7,which latter are of such size as very snugly to contact the innersurface of the tube 1.

A circumferential series of longitudinally arranged ridges, two of whichare marked 9, promote surface contact of this inner skirt 5 iWllh thetube 1 and also strengthen the skint, While the inner edge of the skirtis beveled, as indicated at 10, to facilitate entry of the skirt intothe tube.

Within the inner skirt is a centrally disposed head piece 11 that isfixed in place by four radial wings 12, 12, 12., 12, which arepreferably integral with the skirt; and in this head piece are formed apair of sockets 13, 1-3, designed to receive the ends of swab sticksdenoted by 14, 14, which, as is customary, are intended to have suitableswabs, marked 15, .15, placed on their free ends for the taking ofcultures or specimens from the patient.

The outer skirt of the cap is denoted by 16. It is shorter than theinner skirt, as clearly shown in the drawing, and is adapted loosely tofit the outside of the tube 1, freely sliding over the edge of the tubeand leaving a slight space between it and the latter to permit theinflow of gas to the groove 8 when the tube is being sterilized. Theexterior of the skirt 16 may be milled as indicated in FIGS. 1 and 4, toaid in the manipulation of the cap.

11 preparation for use, the assembled tube and cap, with the latterinserted only partially and the continuous bead Patented Jan. 5, 1965 6'outside the-tube, as shown in FIG. 5, are placed in a container ofcellophane, Mylar, paper or their equivalents, alone or in combination,which is then sealed. This package is enclosed in a chemical retort andsubjected to a relatively high vacuum (e.g., 29 inches) to evacuate mostof the air, both from the package and from the tube (through the groovefi), A sterilizing gas, such, for instance, as ethylene oxide, is nowintroduced into the retort, under pressure, the gas penetrating thecellophane container and seterilizing its interior as well as theinterior of the tube to Whichit' passes through the groove 3.Thereafter, the package is removed from the retort and Will remain inits sterilized condition for storage or shipment until required for use.It should be added that this condition results from the fact thatatmospheric air is not under any pressure tending to force it into thepackage, while sufficient sterilizing gas will remain in the packageeven it" it is compressed somewhat in handling. This procedure is wellunderstood and is described, for instance, in United States Patent No.3,004,681, issued October 17, 1961.

When used, the assembled tube and cap are removed from; the cellophanecontainer, the cap carrying the swab sticks is pulled from the tube andstood upright on the fiat top of the cap. The culture specimen is takenfrom the patient on one or more swabs, after which the sticks arereinserted into the tube and the cap is forced to its fully closedposition with the bead 6 tightly contacting the inner surface of thetube and the underside of the cap pressing on the edge of the tube,zthus completely sealing the latter in condition to be taken to alaboratory for examinaion and testing without danger of contamination.

The use of the tube may be repeated by the insertion of new swab sticksinto the cap, and rte-sterilization as above described, to whichcontinued reuse the article is fully amenable.

As the handling and employment of this article have been explained inthe foregoing description it is deemed superfluous to recite asubstantial repetition, but it may be emphasized that this inventionprovides an inexpenisve and fully satisfactory product for thisimportant field of use.

It should also be understood that various changes may be made in thestructure, material and precise arrangement of the several parts of theclosure Without departing from the spirit and scope of the invention,and hence, i do not intend the coverage of the patent to be limited tothe details hereinabovedescribed except as the same may be included theclaims or be required by disclosure of the prior art.

Vihat I claim is:

1. A closure for a therapeutic test tube designed and adaptedparticularly as a culture container, said closure comprising a top and apair of depending axially aligned shirts one within the other, the innerskirt being fitted for insertion Within the tube and having two externalcircumferential longitudinally spaced beads adapted closely to contactthe tube with a sealing fit, the longitudinally inner bead beinginterrupted while the longitudinally outer one is continuous, togetherwith a longitudinally disposed groove in the exterior of the inner skirtthat extends from the extremity thereof through the longitudinally innerbead but terminates short of the longitudinally outer bead.

2. A closure as defined in claim 1, which is adapted to be partiallyinserted into the tube with the longitudinally inner bead only insealing contact therewith to per tit evacuation of air from the tube andthe filling of the latter with a sterilizing gas.

3. A closure as defined in claim 2, which is also adapted for fartherinsertion into the tube to complete the sealing thereof by thelongitudinally outer bead and the top of the closure.

4. A closure :1 destined in claim 3, in which the outer skirt isslightly elastic to enable it to ride over any enlargement that mayexist at the open end of the tube and is spaced sufficiently from theinner skirt loosely to fit the outside of the tube for permittingevacuation of air and ingress of sterilization gas when the closure ispartially inserted in the tube.

5. A closure as defined in claim 4, which also includes a head piecefixed within the inner skirt and provided with at least one socketadapted removably to receive and hold a swab stick.

6. A closure as defined in claim 1, in which the top is larger in areathan the cross section of the outer skirt and formed with a peripheraledge shaped to prevent rolling of the tube when laid horizontally.

References Cited by the Examiner UNITED STATES PATENTS 2,644,978 7/53Becker 2l54l 2,721,595 10/55 Nichols 215-47 2,991,902 7/61 Lind 215413,005,564 10/61 VJeichselbaum 2l547 3,057,502 10/62 Wood 2l5-47 FOREIGNPATENTS 230,997 5/59 Australia.

FRANKLIN T. GARRETT, Primary Examiner.

1. A CLOSURE FOR A THERAPEUTIC TEST TUBE DESIGNED AND ADAPTEDPARTICULARLY AS A CULTURE CONTAINER, SAID CLOSURE COMPRISING A TOP AND APAIR OF DEPENDING AXIALLY ALIGNED SKIRTS ONE WITHIN THE OTHER, THE INNERSKIRT BEING FITTED FOR INSERTION WITHIN THE TUBE AND HAVING TWO EXTERNALCIRCUMFERENTIAL LONGITUDINALLY SPACED BEADS ADAPTED CLOSELY TO CONTACTTHE TUBE WITH A SEALING FIT, THE LONGITUDINALLY INNER BEAD BEINGINTERRUPTED WHILE THE LONGITUDINALLY OUTER ONE IS CONTINUOUS, TOGETHERWITH A LONGITUDINALLY DISPOSED GROOVE IN THE EXTERIOR OF THE INNER SKIRTTHAT EXTENDS FROM THE EXTREMITY THEREOF THROUGH THE LONGITUDINALLY INNERBEAD BUT TERMINATES SHORT OF THE LONGITUDINALLY OUTER BEAD.